AIIMS 2017 Physics Concave Mirrors MCQ Question

To find the length of the image formed by the concave mirror, we first determine the position of the rod's ends relative to the mirror. The closer end of the rod is at a distance of 20 cm from the mirror, and since the rod is 10 cm long, the farther end is at 30 cm from the mirror. Using the mirror formula $\frac{1}{f} = \frac{1}{v} + \frac{1}{u}$ with $f = -10 \, \text{cm}$ (focal length of a concave mirror), we find the image distances for both ends, resulting in an image length of 5 cm. Other options (2 cm, 4 cm, and 6 cm) do not correspond to the calculated image length based on the mirror's properties and the dimensions of the rod.